Is it possible that your command /dev/ttyUSB0 600,cs7,cstopb,-parenb has an error?
I executed stty 600 then stty -a : denis@denis-ThinkPad-L420:~$ stty -a speed 600 baud; rows 24; columns 80; line = 0; intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>; eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V; discard = ^O; min = 1; time = 0; -parenb -parodd -cmspar cs8 -hupcl -cstopb cread -clocal -crtscts -ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff -iuclc -ixany -imaxbel iutf8 opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0 isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke -flusho -extproc Then I tried stty cs7 and got: denis@denis-ThinkPad-L420:~$ stty cs7 stty: 'standard input': Invalid argument Yet the man page lists csN. Clearly I do not know what I am doing. On Mon, Dec 11, 2017 at 10:35 AM, Denis Heidtmann <[email protected] > wrote: > Tried it. No response. Not sure how I got back to a functioning > terminal, but now: > denis@denis-ThinkPad-L420:~$ sigrok-cli --driver > mastech-mas345:conn=/dev/ttyUSB0 > --scan > sr: serial: Error opening port (16): Device or resource busy. > denis@denis-ThinkPad-L420:~$ > > > On Sun, Dec 10, 2017 at 11:32 PM, Russell Senior < > [email protected]> wrote: > >> The signaling on a PC RS232 line is +nV and -nV, where n is somewhere >> between 5 and 12, inclusive. So, I think -6V would be a zero and a >> +6V would be a one. >> >> I think you can use GNU screen here, with the following options >> (serial parameters are from the manpage from stty(1): >> >> screen /dev/ttyUSB0 600,cs7,cstopb,-parenb >> >> Not sure this is doing the suggested thing for RTS and DTR. >> >> On Sun, Dec 10, 2017 at 8:41 PM, Denis Heidtmann >> <[email protected]> wrote: >> > I notice that 12 V is mentioned. I measure ~6 V from ground to every >> pin >> > except RxD, which is zero. (All DC; when not sending data.) Could this >> be >> > the issue? >> > >> > On Sun, Dec 10, 2017 at 6:28 PM, Denis Heidtmann < >> [email protected]> >> > wrote: >> > >> >> Here is the protocol description I recall finding: >> >> >> >> MAS345: >> >> >> >> data format: 7n2 at 600 baud (7 bits, no parity, 2 stop bits). >> >> Control lines: >> >> DTR and RTS lines are used to power the TX line: RTS is clear >> >> for -12 supply; DTR is set for +12 supply. Data transmission is >> >> solicited sending whatever character to the RX line. >> >> Data string format: >> >> MAS-345 sends a 14 bytes string with: >> >> <mode>< ><sign><value>< ><units><return> >> >> <mode>: two bytes with the oerating mode: DC, AC, OH, CA, TE ... >> >> <sign>: one byte with - or space >> >> <value>: five bytes with four digits and one decimal dot. >> >> <units>: four bytes with the units: mV, A, kOhm, nF ... >> >> <return>: '\r' >> >> One space is inserted between <mode> and <sign>, one between >> >> <value> and <units>. >> >> The data string (without the '\r') is sent to the output device. >> >> >> >> On Sun, Dec 10, 2017 at 6:11 PM, Denis Heidtmann < >> >> [email protected]> wrote: >> >> >> >>> The protocol I recall seeing documented was 7n2, 600 baud. I must >> >>> confess I do not know how to talk directly over serial. I tried >> Google, >> >>> but there were too many options and opinions. What do you recommend >> for >> >>> this simple task? >> >>> >> >>> On Sun, Dec 10, 2017 at 3:01 PM, Russell Senior < >> >>> [email protected]> wrote: >> >>> >> >>>> Try talking to the DMM directly over serial. The protocol >> description >> >>>> says: >> >>>> >> >>>> Various multimeters from Metex (and rebadged ones) use this common >> >>>> 14-byte packet based ASCII protocol. The actual multimeter ICs in the >> >>>> devices have different names (e.g. "MASTECH M343-01" or "Metex >> >>>> KS57C2016") but they all use the same common protocol format. >> >>>> >> >>>> The serial port settings can vary from device to device, e.g. >> >>>> 600/1200 baud, 7n2, RTS low, DTR high. >> >>>> >> >>>> If you get the serial parameters right, you ought to be able to talk >> >>>> directly at it (e.g. send a D and get a string of bytes). Maybe you >> >>>> can snoop the serial with an oscilloscope while running the vendor >> >>>> interface software and figure out the baud,et al. >> >>>> >> >>>> On Sun, Dec 10, 2017 at 2:08 PM, Denis Heidtmann >> >>>> <[email protected]> wrote: >> >>>> > Thanks for the -help. I got part of that -help when I entered an >> >>>> incorrect >> >>>> > option, but somehow missed the -- entries at the end. Here is >> what I >> >>>> get: >> >>>> > >> >>>> > denis@denis-ThinkPad-L420:~$ sigrok-cli --driver >> >>>> > mastech-mas345:conn=/dev/ttyUSB0 --scan >> >>>> > The following devices were found: >> >>>> > mastech-mas345 - MASTECH MAS345 with 1 channel: P1 >> >>>> > >> >>>> > denis@denis-ThinkPad-L420:~$ sigrok-cli --driver >> >>>> > mastech-mas345:conn=/dev/ttyUSB0 --show >> >>>> > mastech-mas345 - MASTECH MAS345 with 1 channel: P1 >> >>>> > Supported driver options: >> >>>> > conn >> >>>> > serialcomm >> >>>> > Supported configuration options: >> >>>> > denis@denis-ThinkPad-L420:~$ >> >>>> > >> >>>> > Additionally I tried: >> >>>> > denis@denis-ThinkPad-L420:~$ sigrok-cli --driver >> >>>> > mastech-mas345:conn=/dev/ttyUSB0 --loglevel 5 >> >>>> > sr: libsigrok loglevel set to 5. >> >>>> > sr: backend: Sanity-checking all drivers. >> >>>> > sr: backend: Sanity-checking all input modules. >> >>>> > sr: backend: Sanity-checking all output modules. >> >>>> > srd: libsigrokdecode loglevel set to 5. >> >>>> > Usage: >> >>>> > sigrok-cli [OPTION...] >> >>>> > snip... >> >>>> > >> >>>> > I also tried the --output-file but nothing. I found that I could >> not >> >>>> enter >> >>>> > more than one option at a time---I tried --scan and --show but >> only the >> >>>> > first one was responded to. >> >>>> > >> >>>> > BTW, recall that this instrument worked as expected using the >> vendor's >> >>>> > windows sw on the desktop, where I have a serial port. So I do not >> >>>> suspect >> >>>> > the hardware outside the laptop. >> >>>> > >> >>>> > These results are encouraging, but no cigar. >> >>>> > >> >>>> > -Denis >> >>>> > _______________________________________________ >> >>>> > PLUG mailing list >> >>>> > [email protected] >> >>>> > http://lists.pdxlinux.org/mailman/listinfo/plug >> >>>> _______________________________________________ >> >>>> PLUG mailing list >> >>>> [email protected] >> >>>> http://lists.pdxlinux.org/mailman/listinfo/plug >> >>>> >> >>> >> >>> >> >> >> > _______________________________________________ >> > PLUG mailing list >> > [email protected] >> > http://lists.pdxlinux.org/mailman/listinfo/plug >> _______________________________________________ >> PLUG mailing list >> [email protected] >> http://lists.pdxlinux.org/mailman/listinfo/plug >> > > _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
